If its static I just use the scales. Don't need really fast shutter speeds. See in the scene how much DoF I might need then set accordingly. If there is something in a foreground say 4 1/2 ft away and say mountains in the distance that needs to be sharp, if I have my 35mm lens, then I would set the scale so the distance on the left side by the 16 on the DoF scale lines up with about 4 1/2 ft and the infinity symbol lines up with the right side of the DoF scale. Then make my exposure. If the lens is woking properly I should be good t ogo. If I look through the view finder it will probably look out of focus. But I know, because I trust the scales, it will be just fine and I should have exceptable focus from about 4 1/2 ft to infinity. So the stuff at 4 1/2 ft will be sharp and the mountains in the background should be also. In that situation it is how much DoF I need that determines what aperture I will choose. If I don't need as much DoF then I will pick a different aperture and still use the scales to make sure I get what I need in focus.
